1. Field of the Invention
The present invention relates to a mechanical shifting transmission system for use in a transmission. More specifically, the present invention relates to a transmission involving a hybrid synchronizing/shifting system to avoid any harsh shift engagement during mechanical shifting of the transmission.
2. Background Information
Automotive transmissions have for many years used fully synchronizing systems. The synchronization of rotational speeds of the driving and the driven gears is of vital importance for the smooth transmission of power and enhanced life and reliable performance of the mating gears. Thus conventional transmission systems as used in automobiles are known to have a synchro ring, usually made of a brass type material. The synchro ring engages with the gear cone seat on the transmission gear during shifting. The synchro ring engages the gear cone seat during shifting to either speed up or slow down the gear that it is engaging so that a smooth transmission is achieved avoiding harsh engagement and achieving a smooth transmission. In some newer transmissions, the synchro ring includes a combination of metal and a composite material on the inside surface. The synchro ring of either type performs the same function which is to up-shift or down-shift gear engagements without grinding of the gear clutch teeth and slider.
In high performance or racing transmissions, the different gear selection is presently known to be achieved by a face shift or dogtooth arrangement. Such dogtooth arrangement when used in isolation provides no synchronization when up or down shifting gears to effect speed/RPM variation. However, such dogtooth arrangement is preferred in racing because the driver can shift rapidly without using the clutch. Nevertheless, the major deficiency in such systems is that the engagement of the dog teeth with the slider is very harsh, subjecting the dogteeth to rapid wear so that the dog tooth and the slider need to be replaced too frequently.
Accordingly, the present invention is directed to a mechanical shifting transmission which avoids such problems associated with rapid wear of dog teeth and/or slider and its frequent replacement.
The present invention thus provides for a mechanical shifting transmission having forward and reverse actuation without any hydraulic pump or clutches and yet avoids undesired harsh shock loading engagement.
More specifically, the present invention makes use of a hybrid synchronization/shifting system for transmission, wherein a selective combination of a synchro ring as well as a dogtooth arrangement is provided to achieve smooth shifting transmission avoiding any harsh engagement thus providing a more efficient mechanical transmission.
Importantly, the transmission system of the present invention achieves the required synchronization of the slider and the gear RPM that enables the face tooth engagement to be less harsh with minimum shock load and thus enhancing the working life of the mating teeth/surfaces.
Thus the primary feature of the present invention is to provide a hybrid synchronized gear shifting arrangement for use in a transmission, for smooth power transmission with forward and reverse speed variation.
Another important feature of the present invention is to make advantageous selective use of both synchro rings and also a dogtooth arrangement to achieve a smooth shifting/transmission in a transmission application avoiding much of the shock load and resultant wear and tear of the related components.
A further important feature of the present invention, is the provision of a hybrid transmission system specifically adapted to synchronize the slider RPM with the speed gear RPM thereby avoiding problems of dog teeth and/or slider wear and frequent replacement.
Another feature of the present invention is to provide a simple, efficient and extended life of a transmission thereby avoiding mechanical failures by avoiding any harsh shock load and engagement of the slider and the speed gear which is normally experienced in the use of conventional dogtooth arrangement based transmission systems.
Other features and advantages of the present invention will be readily apparent to those skilled in the art by a consideration of the detailed description of a preferred embodiment of the present invention contained herein.